Purpose Owing to scalability and cost barriers in vat photopolymerization rapid tooling, this paper aims to investigate a framework for fabricating cost-efficient mould inserts using liquid crystal display-based masked stereolithography (LCD-MSLA) systems and blended open-market photopolymers, accounting for anisotropy, thermo-mechanical robustness and separation–force constraints. Design/methodology/approach A material–architecture–simulation–experimental methodology was developed. A high-temperature photopolymer was blended with a toughening component to tune stiffness within manufacturable limits. Compression testing quantified anisotropy and identified elastic and strength parameters for finite element (FE) models. Rheological simulations defined pressure and loading conditions. A hybrid shell–backfilled insert architecture balanced stiffness and manufacturability in bottom-up MSLA printing. Inserts were validated by moulding trials. Findings Compression testing revealed build-direction anisotropy, with the Z-oriented configuration showing a Young’s modulus of 1892 MPa, yield stress of 45.24 MPa and fracture stress of 84.49 MPa. Rheological simulations predicted filling and packing conditions consistent with trials using mineral-filled polypropylene. Validation demonstrated stable moulding over 40 cycles, cycle time of 69.27 s and a peak injection pressure of 44.2 MPa. FE analyses under worst-case loading predicted stresses below the fracture limit, with no observable structural degradation. Practical implications The results are relevant to industry, designers and researchers, demonstrating that cost-efficient LCD-MSLA platforms combined with open-market photopolymers can produce reliable short-run injection mould inserts for prototyping and low-volume production without high-cost materials or specialised machinery. This helps bridge an industrial gap in rapid tooling accessibility. Originality/value To the best of the authors’ knowledge, this is among the first studies to investigate cost-efficient LCD-MSLA-fabricated injection mould inserts for relatively large tooling geometries using blended open-market photopolymers under coupled manufacturability, thermo-mechanical and structural constraints.

Within the framework of the LIFE-COMP0LIVE project, several innovative polymer-based composite materials reinforced with olive tree pruning wood (OTP) fibre were developed, manufactured and transformed into final demonstrator components. The design of these materials at laboratory scale focused on: (a) meeting the technical requirements proposed by the end-users involved in the project, and (b) presenting a real and more sustainable alternative polymeric materials. Among the materials that successfully met the initial specifications, a recycled polypropylene-based composite material reinforced with up to 40 wt% of OTP fibre stood out, especially due to its great potential for application in the automotive industry. Its manufacture process was scaled up to produce up to a total of 400 kg of biocomposite material in the form of pellets, which were subsequently transformed into automotive parts. To demonstrate the improvement in terms of sustainability, a Life Cycle Assessment (LCA) was conducted for the manufacturing of this biocomposite on an industrial scale -through a cradle-to-gate approach. This resulted in a remarkable reduction of ca. 40 % in the Global Warming Potential respect to the conventional industrial-based virgin polypropylene material -filled with talc (5 wt%), as well as a significant decrease in the endpoint damage categories in the range 48 %-64 %. A sensitivity analysis further showed that these results can even be improved up to 40 % by virtually eliminating the consumption of chemical reagents and using only electricity from renewable sources.

The spread of microorganisms is a global challenge for health, the environment, and the economy. Incorporating antibacterial agents into polymeric materials, such as polylactic acid (PLA), is an effective strategy. This study compared the incorporation of metallic (silver) and photocatalytic (titanium dioxide) fillers in 3D printed objects, evaluating their thermal stability, dispersion, crystalline structure, and antibacterial effectiveness. Various characterization techniques were used, including X-ray microfluorescence (mu FRX), thermal stability, scanning electron microscopy (SEM), transmission electron microscopy (TEM), FT-IR spectroscopy, X-Ray diffraction (XRD), UV spectroscopy, X-ray photoelectron spectroscopy (XPS), and agent migration tests, along with antibacterial efficacy. The UV-activated photocatalytic materials showed a durable 99.99% efficacy against S. aureus and E. coli, emerging as a promising material for applications in medical, food, textile, electronic, and transportation sectors, enhancing hygiene through additive manufacturing.

The stability of edible vegetable oils is strongly affected by packaging. Plastics such as polyethylene terephthalate (PET) are widely used due to cost-effectiveness and practicality, yet their protective capacity under stress conditions is limited. This study examined the degradation of extra-virgin olive oil (EVOO), olive oil (OO), and refined rapeseed oil (RO) stored in PET at 20 degrees C, 40 degrees C, and 60 degrees C, over six weeks, with dark-glass storage at 20 degrees C as control. Quality changes were assessed using physicochemical, sensory, and antioxidant indicators, including free fatty acids (FFA), peroxide value (PV), UV extinction coefficients (K232, K268), sensory analysis (descriptive and via a potentiometric electronic tongue used as a taste device), oxidative stability (Rancimat), and antioxidant potential (DPPH, ABTS, FRAP, and total phenolics). Significant quality degradation was observed with up to a 44 % increase in FFA, a 53 % reduction in TPC, and a 44 % reduction in FRAP. Sensory defects emerged in RO samples, while EVOO retained positive sensory attributes. Oils stored in PET containers exhibited greater susceptibility to oxidation at high temperatures, whereas samples stored in dark glass showed enhanced stability. Predictive discrimination models showed high sensitivity (99 f 4 %-100 %) in accurately classifying edible vegetable oils according to storage conditions when combining physicochemical and sensory data, while E-tongue fingerprints alone achieved satisfactory discrimination (87 f 13 % to 96 f 8 %). Antioxidant activity also declined with thermal stress. Overall, findings highlight that temperature significantly compromises oil stability in PET packaging, underscoring the importance of optimized storage strategies to ensure product safety and quality preservation.

Polylactic acid (PLA) is a widely used bio-based polymer, although its application is limited by mechanical brittleness and low thermal resistance. PLA-based biocomposites reinforced with waste materials are gaining attention due to their sustainability, but their durability under degradation conditions remains a key concern. In this work, PLA biocomposites containing 0, 1, and 3% wt. of Olive-stone Biomass Ash (OBA) were manufactured and characterized both (1) after manufacture and (2) after laboratory-accelerated weathering (including UV exposure, heat, and humidity). The results obtained were analyzed to evaluate the influence of ash incorporation on degradation resistance (measured through Carbonyl Indices, CI), mechanical properties (tensile strength), thermal (Thermogravimetric Analysis-Differential Scanning Calorimetry, TGA-DSC), structure (Fourier Transform Infrared Spectroscopy, FT-IR), morphology (Scanning Electron Microscopy, SEM) and appearance (colorimetry and gloss). Key quantitative findings include a 35% reduction in tensile strength for raw PLA after 1000 h weathering exacerbated to 48% and 50% with 1% and 3% OBA incorporation, respectively. Degradation indices showed increased hydroxyl formation, with HI values ranging from 0.38 to 2.80 for PLA, while for biocomposites HI rose up to 5.85 for PLA with 3% OBA. Subsequently, a solid-state reaction was model-fitted from experimental data obtained by means of TGA analysis for determining the kinetic triplet (pre-exponential factor, the activation energy, and the reaction mechanism). Finally, the Acceleration Factor (AF), which combines the effects of radiation, temperature, and humidity to predict long-term material performance, is addressed analytically.

This research investigates food safety concerns related to contaminants leaching from plastic packaging into food, focusing on the degradation of sunflower, corn, and rapeseed oils stored in polyethylene terephthalate (PET) containers. The study evaluates the effects of heat exposure (40 degrees C and 60 degrees C) and long-term storage (up to 12 months) on the physicochemical properties and sensory qualities of oils purchased from Spain and Germany. The research is divided into two experiments: E1 analyzes oils after heat treatments, and E2 examines them after a year of storage. Heavy metals, such as antimony (Sb), cadmium (Cd), copper (Cu), lead (Pb), and iron (Fe), were detected using advanced mass spectrometry techniques. PET degradation was assessed using Fourier Transform Infrared Spectroscopy (FT-IR/MIR) and Differential Scanning Calorimetry (DSC). Results showed increased acidity, peroxide levels, and sensory degradation, with a rise in "rancid" characteristics after 12 months. PET exhibited chemical changes, including an elevated carbonyl index and amorphization, with copper (Cu) being the most prevalent metal, and Sb levels rising after thermal exposure. This study enhances understanding of how heat and storage affect contaminant migration from PET packaging into seed oils, highlighting implications for food safety and product quality.

In order to reduce energy consumption in buildings, this study used olive pruning sawdust (OTPS) instead of natural sand in the production of lightweight mortars. Different percentages of natural sand substitution were tested: 0, 10, 25, and 50% by volume of sand over 7 and 28 days of curing time. Additionally, the influence of a chemical pretreatment in an aqueous solution of calcium hydroxide on the OTPS was also evaluated to mineralize the wood before its addition to the mortar mixture. Mortars with OTPS incorporations were characterized by volumetric shrinkage, bulk density, and capillary water absorption. Mechanical behavior was tested through compression and flexural tests. The addition of this byproduct decreased bulk density and increased mortar porosity. Pretreating olive pruning sawdust with an aqueous solution of calcium hydroxide was effective for wood mineralization, resulting in physical and mechanical properties superior to mortars without pretreatment. The results showed that a maximum addition of 10% by volume of OTPS treated with calcium hydroxide solution produced lighter mortars with similar mechanical properties to the control mortar. Adding higher amounts of pretreated olive pruning (25–50% by volume) led to a more pronounced deterioration of mechanical properties.

Throughout history, viruses have consistently adapted to survive and spread. Understanding airborne transmission and surface survival emphasizes the necessity for antiviral materials. This study demonstrates virucidal reduction of human Coronavirus 229E and Feline Calicivirus on a polylactic acid and titanium dioxide nanoparticle composite with photocatalytic activity and UV activation. Mechanical properties and UV spectroscopy are also examined, suggesting the potential of the composite in medical and food applications through additive manufacturing.

Olive tree pruning (OTP) is one of the most abundant sources of biomass waste in the Mediterranean basin. This is especially relevant in southern Spain where olive oil production represents a large part of the economy. Olive tree prunings are mostly either burned or are spread in olive orchards as an organic amendment, or used for heat generation on a domestic scale. However, the lignocellulosic composition of OTP makes it a potential source of biopolymers, thus providing an excellent economic alternative for the olive oil sector. In this work, pretreated OTP fibers were subjected to an optimized alkaline treatment followed by a single-step bleaching reaction with H2O2. Afterwards, the cellulose pulp was transformed chemically to obtain cellulose acetate. Noncellulosic components were removed effectively from OTP, thus obtaining a pulp highly purified in cellulose with 71% crystallinity and 355 degrees C maximum degradation temperature. Nevertheless, a very large amount of cellulose (ca. 50%) was eliminated throughout the process, especially during acid pretreatment, which was responsible for 38% solubilization. A similar level of acetylation and degree of substitution was obtained by using acetylation times in the range of 1 to 6 h. No large differences were observed in the infrared spectra and X-ray diffractograms of the synthesized acetates. However, their thermal stability varied significantly with reaction time, evolving from a multistep degradation pattern to a single and sharp peak between 300 and 400 degrees C with increasing time. Thermogravimetric curves revealed that at least 5 h (preferably 6 h) were needed to obtain cellulose acetate from OTP with adequate thermal stability for further processing.

This work highlights the relevance of promoting an entrepreneurial culture in university students through projects developed in the classroom. The main objective is to motivate and train future entrepreneurs, developing practical skills and business knowledge. The main focus is the introduction of mentors in entrepreneurship, with profiles related to the students, to acquire the competence in ‘entrepreneurship’ through conferences, coworking meetings and the use of social networks. The experience has been satisfactory, strengthening collaborations between the university, companies and technology centres. The presence of mentors has motivated students to participate in entrepreneurial initiatives and to orient their coursework towards innovative ideas.

A two-step chemical process was carried out on olive pruning residues according to an optimised sequence that led to the isolation of natural fibre with a high cellulose content. Reaction time, temperature and HNO 3 concentration in the acid hydrolysis stage were optimised by means of the Response Surface Methodology to achieve the highest removal of hemicellulose and lignin and the highest crystallinity index, minimising cellulose hydrolysis. Subsequent hydrolysis with NaOH allowed to obtain a pulp enriched in cellulose (83.28 wt.%). Analysis revealed that the cellulose isolated had a high crystallinity index (70.06%) and thermal stability ( T max = 357°C). The cellulose obtained was finally used for the manufacture of polymer biocomposites and to evaluate its viability as a filler for polymeric materials. The selected polymer matrix used was polylactic acid (PLA) and the amount of filler was 5 and 15% by weight, respectively. In general, the fibres did not improve the mechanical properties of PLA, and maintained unchanged its melting temperature. Microscopic analysis revealed that PLA/fibre adhesion was stronger for treated fibres. Contradictorily, the composites with untreated fibres presented slightly higher thermal stability. Water uptake increased with the concentration of fibres, being higher in those materials with untreated fibre.

In this study, the integration of paper industry waste with high cellulose content into biocomposites of polylactic acid (PLA), a widely used biobased polymer material, was investigated. The PLA/waste biocomposite samples (0–25 wt.%) were manufactured using the extrusion and injection moulding techniques. The mechanical test results showed improvements in terms of tensile properties and a decrease in impact strength as the percentage of residue increased. The melting temperature decreased, and the crystallinity increased in all biocomposites according to the Differential Scanning Calorimetry (DSC) analysis. Water absorption increased proportionally with the percentage of residue, attributed to the higher cellulose content in the biocomposites, determined by Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques. The scanning electron microscopy (SEM) fracture analysis demonstrated effective reinforcement–matrix cohesion, supporting the previously observed behaviour of the analysed materials. This work highlights the potential of using waste from the paper industry as reinforcement in PLA matrices, opening new perspectives for sustainable applications in the framework of the manufacture of composite materials.

This research examines the mechanical characteristics of polylactic acid (PLA) using a variety of experimental approaches, including analyses of printing orientations and the application of advanced methodologies such as digital image correlation (DIC) for accurate assessment of deformation, along with scanning electron microscopy (SEM) to evaluate fracture properties. Tensile strength, flexural, impact strength, compressive and shear strength were characterized in detail, highlighting the critical impact of layer deposition direction. These findings provide valuable information for optimizing orientation selection in specific additive manufacturing contexts, emphasizing the need to address anisotropy in 3D printed materials engineering.

Throughout history, viruses have consistently adapted to survive and spread. Understanding airborne transmission and surface survival emphasizes the necessity for antiviral materials. This study demonstrates virucidal reduction of human Coronavirus 229E and Feline Calicivirus on a polylactic acid and titanium dioxide nanoparticle composite with photocatalytic activity and UV activation. Mechanical properties and UV spectroscopy are also examined, suggesting the potential of the composite in medical and food applications through additive manufacturing.

Appears in: INTED2024 Proceedings Publication year: 2024Pages: 7008-7013ISBN: 978-84-09-59215-9ISSN: 2340-1079doi: 10.21125/inted.2024.1857Conference name: 18th International Technology, Education and Development ConferenceDates: 4-6 March, 2024Location: Valencia, Spain

IMPLEMENTING CONTENT CURATION AS A STRATEGY FOR INTEGRATING THE SUSTAINABLE DEVELOPMENT GOALS (SDGS) INTO MATERIALS SCIENCE COURSES